KR101484993B1 - Apparatus and method for joint encoding of user specific reference signal information in wireless communication - Google Patents

Abstract

An apparatus and method are provided for providing encoded information associated with a user-specific reference signal associated with a user equipment in a multiple access wireless communication system. The encoded information jointly displays the transmit rank together with at least one parameter associated with a user-specific reference signal, e.g., a set of antenna ports and a user-specific reference signal pattern. Encoded information is transmitted on the downlink control channel to reduce overhead in the downlink control channel.

Description

[0001] APPARATUS AND METHOD FOR JOINT ENCODING OF USER SPECIFIC REFERENCE [0002] SIGNAL INFORMATION IN WIRELESS COMMUNICATION [0003]

This application claims priority to U.S. Provisional Patent Application No. 61 / 257,376, filed November 2, 2009, which is incorporated herein by reference in its entirety.

The present application relates generally to multi-access wireless communications. More specifically, but not exclusively, the present application is directed to techniques for encoding user-specific reference signal information in a multi-access wireless communication system.

Wireless communication systems are widely deployed to provide various types of communication content such as voice, data, and so on. These systems may be multi-access systems capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth and transmit power). Examples of such multi-access systems include Code Division Multiple Access ("CDMA") systems, Time Division Multiple Access ("TDMA") systems, Frequency Division Multiple Access ("FDMA") systems, 3GPP Long Term Evolution ") Systems and orthogonal frequency division multiple access (" OFDMA ") systems.

In general, a wireless multiple-access communication system can simultaneously support communications for multiple wireless terminals. Each terminal communicates with one or more base stations via transmissions on the forward and reverse links. The forward link (or downlink) refers to the communication link from the base stations to the terminals, and the reverse link (or uplink) refers to the communication link from the terminals to the base stations. Such communication links may be established through a single-input single-output, multiple-input single-output or multiple-input multiple-output ("MIMO") system.

A MIMO system uses multiple ("N _T ") transmit antennas and multiple ("N _R ") receive antennas for data transmission. A MIMO channel formed by N _T transmit and N _R receive antennas may be decomposed into N _S independent channels, which are also referred to as spatial channels, where N _S < min {N _T , N _R }. Each of the N _S independent channels corresponds to a dimension. A MIMO system may provide improved performance (e.g., higher throughput and / or greater reliability) when additional dimensions generated by multiple transmit and receive antennas are used .

The MIMO system supports both time division duplex ("TDD") and frequency division duplex ("FDD") systems. In a TDD system, the forward and reverse link transmissions are in the same frequency domain so that the principle of reciprocity enables estimation of the forward link channel from the reverse link channel. This allows the access point to extract the transmit beamforming gain on the forward link when multiple antennas are available at the access point.

In general, wireless cellular communication networks incorporate multiple mobile user equipments ("UEs") and multiple base nodes ("NodeBs"). The NodeB is generally a fixed station and may also be referred to as a base transceiver system ("BTS"), an access point ("AP"), a base station ("BS") or some other equivalent term. As enhancements to the networks are made, the NodeB functionality evolves so that the NodeB is also sometimes referred to as an improved NodeB ("eNB"). In general, NodeB hardware is fixed and stopped when deployed, while UE hardware is portable.

In contrast to NodeB, mobile UEs may include portable hardware. A UE, also commonly referred to as a terminal or mobile station, may be a stationary or mobile device and may be a wireless device, a cellular telephone, a personal digital assistant ("PDA"), a wireless modem card, The downlink ("DL") refers to the communication from the NodeB to the mobile UE, while the uplink communication ("UL") refers to communication from the mobile UE to the NodeB.

Each Node B includes radio frequency transmitter (s) and receiver (s) used to communicate directly with mobile UEs that are free to move around. Similarly, each mobile UE includes radio frequency transmitter (s) and receiver (s) used to communicate directly with the NodeB. In cellular networks, mobile UEs can not communicate directly with each other, but must communicate with the NodeB.

The reference signal ("RS") is a predefined signal previously known to both the transmitter and the receiver. The RS can generally be thought of deterministically in terms of both the transmitter and the receiver. Typically, the RS is transmitted to allow the receiver to estimate the signal propagation medium. This process is also known as "channel estimation ". Thus, the RS may be transmitted to facilitate channel estimation. In deriving the channel estimates, these estimates are used for demodulating the transmitted information. This type of RS is sometimes referred to as demodulating RS or DM-RS. It should be noted that the RS may also be transmitted for other purposes such as channel sounding (sounding reference signal or "SRS"), synchronization, or any other purpose. It should also be noted that RS may sometimes be referred to as a pilot signal, a training signal, or any other equivalent term.

In many modern communication systems, the DM-RS may be specific to the UE (referred to herein as "UE-RS" or user-specific reference signal). For example, releases 9 and 10 of LTE relies on UE-RSs for demodulation. Different spatial processing techniques may be used in more recent releases of LTE such as single-user MIMO ("SU-MIMO") and cooperative with up to 8 transmission layers and coordinated across multiple cells and nodes in the network Quot; multi-user MIMO ("MU-MIMO") operation. Cooperation may be at the level of beam coordination where the transmission point for each user is still in one cell, or co-operation may be performed by a joint transmission where a data packet for a particular UE is transmitted from multiple cells ≪ / RTI > The UE-RSs play an important role in enabling efficient operation under these different spatial processing techniques.

In addition, the UE-RSs provide local channel estimates between the resources allocated to the UEs to the UEs and are treated as being transmitted on their own channel responses using a separate antenna port. A typical use of a UE-RS is to enable beamforming of data transmission to specific UEs. For example, rather than using the physical antennas used for transmission of other (cell-specific) antenna ports, the eNodeB may use a correlated array of physical antenna elements to generate a narrow beam in the direction of a particular UE. Such a beam may experience different channel responses between the eNodeB and the UE, thus requiring the UE to use UE-specific RSs to coherently demodulate beamformed data.

In order for the UE to be able to perform demodulation and decoding of the transmitted data, the UE-RS information needs to be delivered to the UE. This information enables the UE to know the resource elements ("REs") that are used for data symbols among other procedures and to perform channel and interference estimation. Therefore, a scheme for efficiently transmitting the UE-RS information to the UE is needed. The present application addresses these issues.

This disclosure generally relates to apparatus and methods for encoding user-specific reference signal information in a multi-access wireless communication system. The information may include, for example, an indication of a user-specific reference signal pattern, a transmission rank, and a set of antenna ports. The information encoded in the downlink control channel is transmitted to reduce overhead in the downlink control channel.

In an aspect, the present disclosure is directed to a method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment. The bit sequence is included in the encoded information to jointly provide an indication of the transmission rank with at least one parameter associated with a user-specific reference signal. The encoded information is transmitted within the payload of the downlink control channel.

In another aspect, this disclosure is directed to a method for wireless communication. The encoded information associated with the user-specific reference signal associated with the user equipment is received on the downlink control channel. The encoded information includes a bit sequence that jointly encodes an indication of a transmission rank with at least one parameter associated with a user-specific reference signal. The encoded information is decoded at the user equipment.

In another aspect, this disclosure is directed to an apparatus for wireless communication. The apparatus comprises means for selecting a user-specific reference signal parameter, means for jointly encoding the selected user-specific reference signal parameter with at least one associated user-specific reference signal parameter, And means for transmitting the encoded user-specific reference signal parameters to the user equipment associated with the user-specific reference signal.

In another aspect, this disclosure is directed to an apparatus for wireless communication. The apparatus comprises means for receiving, on a downlink control channel, encoded information associated with a user-specific reference signal associated with the UE, wherein the encoded information includes at least one parameter associated with a user- Comprising: a bit sequence that is jointly encoded; And means for decoding the encoded information.

In another aspect, the present application is directed to an apparatus for wireless communication. The apparatus comprises means for receiving, on a downlink control channel, encoded information associated with a user-specific reference signal associated with the UE, and the encoded information communicating an indication of a transmission rank with at least one parameter associated with a user- A sequence of bits for encoding; And a processor configured to decode the encoded information.

In a further aspect, the present disclosure includes a computer readable storage medium and computer program product for use in a wireless communication system. The computer-readable storage medium includes instructions for causing at least one computer to select a transmission rank, instructions for causing at least one computer to associate a selected rank with at least one parameter associated with a user- And instructions for causing at least one computer to provide a rank and a joint indication of the at least one parameter to reduce overhead in the downlink control channel.

In another aspect, the present disclosure is directed to an apparatus that facilitates provision of encoded information associated with a user-specific reference signal associated with a user equipment. The apparatus comprises a bit sequence for jointly encoding an indication of a transmission rank in the encoded information with at least one parameter associated with a user-specific reference signal, and transmitting the encoded information within the payload of the downlink control channel ≪ / RTI >

In another aspect, the present disclosure is directed to a computer program product comprising a computer-readable storage medium and facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment. The computer readable storage medium having instructions for causing at least one computer to include in the encoded information a bit sequence that at least encodes an indication of a transmission rank with at least one parameter related to a user- And instructions for causing at least one computer to transmit the encoded information in a payload of the downlink control channel.

In a further aspect, the invention relates to a method for facilitating the provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). The transmission rank is selected. The selected transmission rank is associated with at least one parameter associated with a user-specific reference signal (UE-RS). A set of scheduling constraints is provided to reduce the signaling overhead in the downlink control channel. The common indication of the rank and the at least one parameter is then transmitted on the downlink control channel subject to a set of scheduling constraints.

In a further aspect, the disclosure is directed to an apparatus that facilitates provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). The apparatus comprising: means for selecting a transmission rank; Means for associating a transmission rank with at least one parameter associated with a user-specific reference signal (UE-RS); Means for providing a common indication of rank and at least one parameter, subject to a set of scheduling constraints, the set of scheduling constraints being selected to reduce overhead in the downlink control channel; And means for transmitting a common indication within the downlink control channel.

In another aspect, this disclosure is directed to a method of facilitating wireless communication in a user equipment (UE). The method includes receiving a joint indication of at least one scheduling parameter and at least one parameter associated with a user-specific reference signal (UE-RS); And performing a channel or interference estimate based at least in part on the at least one scheduling parameter.

In another aspect, this disclosure is directed to an apparatus that facilitates wireless communication at a user equipment (UE). The apparatus comprising: means for receiving a joint indication of at least one scheduling parameter and at least one parameter associated with a user-specific reference signal (UE-RS); And means for performing channel or interference estimation based at least in part on the at least one scheduling parameter.

The present disclosure further relates to computer program products, devices, devices and systems for implementing the methods described above, as well as others described herein. Various additional aspects are further described below in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The present application will be more fully appreciated with reference to the following detailed description, taken in conjunction with the accompanying drawings, wherein like reference numerals designate the same elements throughout:
Figure 1 illustrates a multiple access wireless communication system in which exemplary embodiments may be implemented;
2 shows a block diagram of an embodiment of a MIMO communication system:
Figure 3 shows exemplary patterns for a UE-RS;
4 shows a flow diagram of a process for delivering UE-RS parameters to a UE; And
5 shows a flow diagram of an exemplary embodiment of a joint encoding of UE-RS parameters.

Devices and methods for facilitating wireless communications are disclosed. The apparatuses and methods may comprise selecting one or more UE-RS parameters associated with a UE-RS for a given UE at the transmitting node, among other procedures, selecting UE-RS parameters to reduce overhead, , Transmitting the encoded information to the UE, decoding the encoded information at the UE to derive UE-RS parameters, and using derived UE-RS parameters to perform channel and interference estimation. Lt; / RTI >

("CDMA") networks, time division multiple access ("TDMA") networks, frequency division multiple access ("FDMA") networks, orthogonal FDMA ("OFDMA") networks, single-carrier FDMA ("SC-FDMA") networks as well as other communication networks. As described herein, the terms "networks" and "systems" are often used interchangeably.

CDMA networks may implement radio technologies such as Universal Terrestrial Radio Access ("UTRA"), CDMA2000, and the like. UTRA includes wideband-CDMA ("W-CDMA") and low chip rate ("LCR"). CDMA2000 covers IS-2000, IS-95 and IS-856 standards. The TDMA network may implement radio technologies such as Global System for Mobile Communications ("GSM").

The OFDMA network may implement radio technologies such as enhanced UTRA ("E-UTRA"), IEEE 802.11, IEEE 802.16, IEEE 802.20, Flash-OFDM, UTRA, E-UTRA, and GSM are part of the Universal Mobile Telecommunications System ("UMTS"). In particular, Long Term Evolution ("LTE") is a future release of UMTS using E-UTRA. UTRA, E-UTRA, GSM, UMTS and LTE are described in documents from the organization named "3rd Generation Partnership Project (3GPP) ", CDMA2000 is referred to as 3GPP2 ≪ / RTI >

These various radio technologies and standards are known in the art. For clarity, certain aspects of the apparatus and methods are described below for LTE, and LTE terminology is used in much of the description below, but the description is not intended to be limiting to LTE applications. Thus, it will be appreciated by those skilled in the art that the apparatus and methods described herein may be applied to a variety of communication systems and applications.

Single carrier frequency division multiple access ("SC-FDMA") using single carrier modulation and frequency domain equalization is a communication technique of interest. SC-FDMA has similar performance and essentially the same overall complexity as OFDMA. However, the SC-FDMA signal has a lower peak-to-average power ratio ("PAPR") than the OFDMA signal due to its inherent single carrier structure. As a result, SC-FDMA has recently attracted a great deal of attention, especially for uplink communications where the lower PAPR is of significant benefit to the mobile terminal in terms of transmit power efficiency. The use of SC-FDMA is the current working assumption for uplink multiple access schemes in 3GPP Long Term Evolution ("LTE") or E-UTRA.

Logical channels in wireless communication systems may be classified as control channels and traffic channels. The logical control channels include a broadcast control channel ("BCCH"), a downlink ("DL") channel for broadcasting system control information, a paging control channel To-multipoint DL channel used to transmit Multimedia Broadcast and Multicast Service ("MBMS") scheduling and control information for some multicast traffic channel (s) Control channel ("MCCH"). In general, after establishing a radio resource control ("RCC") connection, such a channel may only be used by UEs receiving the MBMS. A dedicated control channel ("DCCH") is also a point-to-point bidirectional channel that transmits dedicated control information and is used by UEs with RRC connections.

The logical traffic channels include a dedicated traffic channel ("DTCH") which is a point-to-point bi-directional channel dedicated to one UE for transmission of user information and an MTCH which is a point- can do.

The transport channels may be classified into a downlink ("DL") and an uplink ("UL"). The DL transport channels may include a broadcast channel ("BCH"), a downlink shared data channel ("DL- SDCH") and a paging channel ("PCH"). The PCH is used for the support of UE power saving (e.g., when the DRX cycle is indicated by the network to the UE), a physical layer that is broadcast over the entire cell and can be used for other control / traffic channels ("PHY") resources. The UL transport channels may include a random access channel ("RACH"), a request channel ("REQCH"), an uplink shared data channel ("UL- SDCH") and a plurality of PHY channels. The PHY channels may include DL channels and a set of UL channels.

Additionally, the DL PHY channels may include the following channels:

The common pilot channel ("CPICH &

Synchronization channel ("SCH")

Common Control Channel ("CCCH")

Shared DL control channel ("SDCCH")

Multicast control channel ("MCCH")

Shared UL Assignment Channel ("SUACH")

Acknowledgment channel ("ACKCH")

DL Physical Shared Data Channel ("DL-PSDCH")

UL Power Control Channel ("UPCCH")

Paging indicator channel ("PICH")

Load indicator channel ("LICH")

The UL PHY channels may in turn include the following set of channels:

Physical random access channel ("PRACH")

Channel quality indicator channel ("CQICH")

Acknowledgment channel ("ACKCH")

Antenna subset indicator channel ("ASICH")

Shared request channel ("SREQCH")

UL Physical Shared Data Channel ("UL-PSDCH")

Broadband pilot channel ("BPICH")

For the purposes of illustration or description, the following terms and abbreviations may be used herein:

AM (acknowledged mode: Acknowledged Mode)

AMD (Acknowledged Mode Data)

ARQ (Automatic Repeat Request)

BCCH (Broadcast Control Channel)

BCH (Broadcast Channel)

C- (Control-: Control-)

CCCH (Common Control Channel)

CCH (Control Channel)

CCTrCH (Coded Composite Transport Channel)

CP (cyclic prefix)

CRC (Cyclic Redundancy Check)

CTCH (Common Traffic Channel)

DCCH (Dedicated Control Channel)

DCH (Dedicated Channel)

DL (Downlink)

DSCH (Downlink Shared Channel)

DTCH (Dedicated Traffic Channel)

DCI (Downlink Control Information)

FACH (forward link access channel)

FDD (Frequency Division Duplex)

L1: Layer 1 (physical layer)

L2: Layer 2 (data link layer)

L3: Layer 3 (network layer)

LI (Length Indicator)

LSB (Least Significant Bit)

MAC (Medium Access Control)

MBMS (Multimedia Broadcast Multicast Service)

MCCH (MBMS Point-to-Multipoint Control Channel)

MRW (Move Receiving Window)

MSB (Most Significant Bit)

MSCH (MBMS Point-to-Multipoint Scheduling Channel)

MTCH (MBMS Point-to-Multipoint Traffic Channel)

The PCCH (Paging Control Channel)

PCH (Paging Channel)

PDU (Protocol Data Unit)

PHY (physical layer)

PhyCH (Physical Channels)

RACH (Random Access Channel)

RLC (Radio Link Control)

RRC (Radio Resource Control)

Service Access Point (SAP)

SDU (Service Data Unit)

SHCCH (Shared Channel Control Channel)

SN (Sequence Number)

SUFI (Super Field)

TCH (Traffic Channel)

TDD (Time Division Duplex)

TFI (Transport Format Indicator)

TM (Transparent Mode)

TMD (Transparent Mode Data)

TTI (Transmission Time Interval)

U- (User: User-)

UE (User Equipment)

UL (Uplink)

UM (Unacknowledged Mode)

UMD (Unacknowledged Mode Data)

UMTS (Universal Mobile Telecommunications System)

UTRA (UMTS Terrestrial Radio Access)

UTRAN (UMTS Terrestrial Radio Access Network)

MBSFN (Multicast Broadcast Single Frequency Network)

MCE (MBMS coordinating entity: MBMS coordinating entity)

MCH (Multicast Channel)

DL-SCH (Downlink Shared Channel)

MSCH (MBMS Control Channel)

PDCCH (Physical Downlink Control Channel)

PDSCH (Physical Downlink Shared Channel)

PCFICH (Physical Control Format Indicator Channel)

It is recognized that the term "exemplary" is used herein to mean "serving as an example, instance, or illustration. &Quot; Any embodiment described herein as "exemplary " is not necessarily to be construed as preferred or advantageous over other embodiments.

Referring now to Figure 1, a multiple access wireless communication system in accordance with an exemplary embodiment is illustrated. In various implementations, an access point ("AP"), such as AP 100 of FIG. 1, may be a fixed station used for communicating with access terminals and may include an access point, NodeB, eNodeB, home eNobeB Or other terms. An access terminal ("AT") such as AT 116 or AT 122 in FIG. 1 may be referred to as an access terminal, user equipment ("UE"), wireless communication device, terminal, ATs 116 and 122 and UE 100 may be configured to implement various aspects of embodiments as described herein.

The access point 100 includes a plurality of antenna groups, one antenna group includes 104 and 106, another antenna group includes 108 and 110, and an additional antenna group includes 112 and 114. [ In Figure 1, although only two antennas are shown for each group of antennas, more or fewer antennas may be used for each group of antennas in various embodiments.

 An access terminal 116 communicates with antennas 112 and 114 where antennas 112 and 114 transmit information to AT 116 over forward link 120 and transmit information from AT 116 And receives via reverse link 118. An access terminal 122 communicates with antennas 106 and 108 where antennas 106 and 108 transmit information to AT 122 over forward link 126 and receive information from AT 122 And receives via reverse link 124. In the FDD system, the communication links 118, 120, 124 and 126 may use different frequencies for communication between the AP 100 and the ATs 116 and 122. For example, the forward link 120 may use a frequency that is different from the frequency used by the reverse link 118. Likewise, links 124 and 126 may use different frequencies from each other and / or from links 118 and 120.

Each group of antennas and / or an area designed to communicate with them may be referred to as a sector of the access point. In the illustrated exemplary embodiment, the groups of antennas are each designed to communicate with the access terminals in a designated sector of the area covered by the access point 100. For example, an antenna group including antennas 112 and 114 may be assigned to a sector designated as sector 1 in FIG. 1, while an antenna group including antennas 106 and 108 may be assigned as a sector 2 Lt; / RTI >

In communications over the forward links 120 and 126, the transmit antennas of the access point 100 are configured to transmit the signal-to-noise ratios of the forward links to the different access terminals 116 and 122, as well as others (not shown) Lt; RTI ID = 0.0 > beamforming. ≪ / RTI > Also, in typical implementations, an access point that uses beamforming to transmit to access terminals that are randomly distributed across the coverage area of the access point may be a wireless access point that transmits to all its access terminals via a single antenna, May cause less interference to the access terminals of more neighboring cells. It is appreciated that precoding of the transmitted signals can be used to facilitate beam formation.

2 is a block diagram of an embodiment of a transmitter system 210 (i.e., access point 210) and receiver system 250 (i. E., Access terminal 250) in an exemplary MIMO system 200 Fig. It is recognized that the transmitter system 210 and the receiver system 250 may correspond to the AP 100 and the ATs 116 and 122 of FIG.

The creation and use of a user-specific reference signal ("UE-RS") as described herein may provide advantages in various MIMO system implementations. It is understood that certain advantages are not necessarily required in all embodiments disclosed herein. The UE-RSs may be generated in one or more modules of the AP 210 for transmission to the AT 250. [ AT 250 may include one or more modules for receiving UE-RSs to estimate channel characteristics and / or to demodulate received data. This may be done in a reference signal selection module that includes one or more components of AP 210 (or other components not shown) such as processors 214 and 230 and memory 232. AP 210 may also include a transmission module that includes one or more components of AP 210, such as transmission modules 224 (or other components not shown). The AP 210 may also include a reference signal pattern generation module that includes one or more components of the AP 210 (or other components not shown). Similarly, AT 250 may include a receiving module that includes one or more components of AT 250, such as receivers 254 (or other components not shown). AT 250 also includes a channel estimation module including one or more components (or other components not shown) of AT 250, such as processors 260 and 270 and memory 272 . The memories 232 and 272 may be used to store computer code for execution on one or more processors to implement processes as described herein.

In operation, at the transmitter system 210, traffic data for a number of data streams may be provided from a data source 212 to a transmit ("TX") data processor 214, where the traffic data is processed May be transmitted to one or more receiver systems (250). In one embodiment, each data stream is processed and transmitted via a respective transmit antenna (e.g., antennas 224a-224t). TX data processor 214 receives, formats, codes, and interleaves the traffic data for each data stream based on a particular coding scheme selected for each data stream to provide coded data.

In particular, as described in more detail below herein, the transmitter system 210 may be configured to use different transmission ranks (i.e., the number of spatial transmission layers and the number of columns in the precoding matrix) RS patterns for different channels and AT 250 states such as time and frequency sensitivity, sub-frame format, and so on, as well as for efficient transmission of selected patterns and other UE-RS parameters for transmission on the downlink control channel . ≪ / RTI > In certain embodiments, an efficient indication may be provided by co-encoding of various UE-RS parameters.

The coded data for each data stream may be multiplexed with the pilot data using OFDM techniques. The pilot data is typically a known data pattern that is processed in a known manner and can be used in the receiver system to estimate the channel response. The pilot data is provided to a TX data processor 214, as shown in FIG. 2, and may be multiplexed with the coded data. The multiplexed pilot and coded data for each data stream may then be combined with a particular modulation scheme (e.g., BPSK, QSPK, M-PSK, M-QAM, etc.) selected for each data stream to provide modulation symbols (I.e., symbol-mapped) based on the received signal. The data rates, coding, and modulation for each data stream may be stored in memory 232 or by processor 230 based on instructions stored in another memory or instruction storage medium (not shown) of transmitter system 210 May be determined by the instructions being performed.

The modulation symbols for all data streams may then be provided to a TX MIMO processor 220 and the TX MIMO processor 220 may further process the modulation symbols (e.g., for OFDM). The TX MIMO processor 220 may then provide Nt modulation symbol streams to Nt transmitters ("TMTR ") 222a through 222t. In certain embodiments, TX MIMO processor 220 may apply beamforming weights to symbols of data streams, which correspond to one or more antennas that transmit symbols.

Each transmitter sub-system 222a through 222t receives and processes a respective symbol stream to provide one or more analog signals and to further condition (e. G., Amplify, filter and < Upconverted) to provide a modulated signal suitable for transmission over the MIMO channel. Thereafter, Nt modulated signals from the transmitters 222a through 222t are transmitted from Nt antennas 224a through 224t, respectively.

In the receiver system 250, the transmitted modulated signals are received by Nr antennas 252a through 252r and the signals received from each antenna 252 are received by respective receivers ("RCVR") 254a through 254r ). Each receiver 254 conditions (e.g., filters, amplifies, and downconverts) each received signal, digitizes the conditioned signal to provide samples, and further processes the samples to generate a corresponding " And provides a symbol stream.

RX data processor 260 then receives and processes Nr received symbol streams from Nr receivers 254a through 254r based on a particular receiver processing technique to provide Nt "detected" symbol streams. The RX data processor 260 then demodulates, deinterleaves, and decodes each detected symbol stream to recover the traffic data for the data stream. The processing by RX data processor 260 is typically complementary to the processing performed by TX MIMO processor 220 and TX data processor 214 in transmitter system 210. [

The processor 270 may periodically determine a precoding matrix. The processor 270 may then formulate a reverse link message that may include a matrix index portion and a rank value portion. In certain embodiments, the reverse link message may include various types of information regarding the communication link and / or the received data stream. The reverse link message may then be processed by a TX data processor 238, which may also receive traffic data for a number of data streams from a data source 236, and the reverse link message is then transmitted to the modulator 280 Modulated by transmitters 254a through 254r, and transmitted back to transmitter system 210. [

Signals modulated from the receiver system 250 are received by the antennas 224 and transmitted to the receivers 222 in order to extract the reverse link messages transmitted by the receiver system 250, Demodulated by the demodulator 240, and processed by the RX data processor 242. The processor 230 then determines what precoding matrix to use to determine the beamforming weights and then processes the extracted message.

It is appreciated that a channel structure may be used that preserves the low PAPR of a single carrier waveform (e.g., at any given time, the channel is adjacent or evenly spaced in frequency) properties. It is also appreciated that the UE-RS may undergo some precoding operation experienced by data symbols.

In certain embodiments, the UE-RS pattern may be selected according to the transmission rank, and different channel and UE states such as channel time and frequency sensitivity, subframe format, and the like.

3 shows exemplary UE-RS patterns for up to four transmission layers in LTE Release 10 for regular cyclic prefix ("CP") subframes. Each square in FIG. 3 represents a resource division element ("RE"), and each shaded area represents a code division multiplex ("CDM ") group that multiplexes two UE-RS ports. For example, in the case of rank 2 transmissions, the two UE-RS ports reside in black shaded REs that are multiplexed in the CDM scheme. In another example, for a rank 4 transmission, there are four UE-RS ports, two are in black REs 300, two are in gray shaded REs 302 exist.

In order for the UE to be able to perform demodulation and decoding of data, the UE may perform at least one of the following: (1) UE-RS pattern; (2) UE-RS port locations; And (3) some UE-RS parameters, such as the UE-RS port for locating the mapping. This information may enable the UE to know the UEs used for data symbols among other procedures and to perform channel and interference estimation. As will be described below, when transmitting these and other UE-RS parameters in the downlink control channel, the parameters can be jointly encoded to reduce overhead.

Referring now to FIG. 4, a flow diagram illustrating a process for delivering UE-RS parameters to a UE is described. First, one or more UE-RS parameter (s) are selected (400). Selected parameters include, for example: (1) a set of UE-RS antenna ports used for transmission to the UE; (2) UE-RS pattern; (3) transmission rank; (4) UE-RS sequence initialization parameters such as UE-RS sequence initialization ID; And (5) the total number of UE-RS ports allocated to all UEs (e.g., in MU-MIMO or Cooperative MIMO across cells). For example, the transmit rank may be selected prior to the UE-RS pattern to provide an indication of the selected rank and antenna ports. In addition, information such as the total number of layers (including all UEs) may also be included between UE-RS parameters.

In certain embodiments, knowledge of these parameters may be utilized through static, semi-static and dynamic signaling, or a combination thereof. For example, in static signaling, the UE may exclude patterns that exceed a certain rank based on the number of antenna ports that are signaled at the PBCH. In quasi-static signaling, a subset of UE-RS antenna ports may be signaled to the UE. The scheduler may then send data to the UE using antenna ports from this subset. The sequence used for UE-RS transmission may also be displayed in a quasi-static manner. Also, in the case of dynamic signaling, the UE-RS pattern can be signaled via DL acknowledgment.

It is recognized that, in the design of the signaling mechanism, the flexibility of scheduling and the associated overhead can be taken into account. For example, legacy LTE downlink control information ("DCI") provides control information regarding transmissions to the UE, such as transmission rank, precoding information, packet format, HARQ,

In certain embodiments, the UE-RS parameters are jointly encoded 405 to the extent possible to reduce overhead in DL control signaling and to detect redundancy present between UE-RS parameters. For example, the UE-RS antenna ports used for transmission may indicate transmission ranks. This redundancy can be used to reduce overhead. After the UE-RS parameters are encoded, they are transmitted 410 on the downlink control channel and decoded at the UE. The UE then demodulates and decodes the data transmitted using the derived UE-RS parameters and the transmitted UE-RS.

FIG. 5 is a flow diagram illustrating in greater detail an exemplary embodiment of the co-encoding 405 of FIG. First, the selected UE-RS pattern is encoded into a given number of bits, e.g., 500 for a maximum rank of 4 transmissions. An allocation is then made between a given transmission rank and a set of antenna ports (505), by considering that some restrictions on signaling do not affect the flexibility of the scheduler operation. For example, assuming that UE-RS antenna ports have similar and symmetrical properties (e.g., density, structure), the first three antenna ports or the rank 3 The transmission is the same. Thus, the restriction of rank 3 transmissions occurring only in the first three UE-RS antenna ports can reduce overhead in signaling without any performance and flexibility impact.

In one example, the transmission rank may be indicated using independent bits from the UE-RS pattern and UE-RS antenna ports bits. This is an extension of the LTE Release 8 DCI format. For a system with operation for the maximum rank 4 and two UE-RS patterns as shown in FIG. 3, two bits can be used to indicate the rank, indicating which UE-RS pattern is used 1 bit may be used and 4 bits may be used to indicate UE-RS antenna ports, resulting in a total of 7 bits being used.

Considering this example, depending on the symmetric structure of the UE-RS ports of FIG. 3, UE-RS antenna port indexes assigned to the UE may be used to determine the maximum number of UE-RS ports available in the UE- (Modulo)) can be ascertained. In this case, the encoding of this information may require an indication of the starting UE-RS port index and the transmission rank. Thus, in this example, one bit is required to encode the UE-RS pattern, two bits are required to encode the rank, two bits are required to encode the starting UE-RS antenna port, Bits are needed.

Alternatively, it is possible to formulate a joint assignment using an indication of antenna port indices and rank information. In this case, the number of UE-RS ports used for the UE-RS determines the number of transmission layers (i.e., rank) to the UE. For example, by indexing antenna ports from 0, 1, 2 to N (the total number of available ports), the following joint assignments of rank and antenna ports can be made:

Rank

Antenna ports
Encoding assignments
Rank 1
{0}, {1}, {2}, or {3}
4 rank / antenna ports assignments

Rank 2

{0, 1} or {2, 3}
2 rank / antenna ports assignments
Rank 3

{0, 1, 2}
1 rank / antenna ports assignments
Rank 4

{0,1,2,3,4}
1 rank / antenna ports assignments

Table 1 - Common ranks / antenna ports assignments

Thus, these eight rank and antenna port assignments may be jointly encoded with three bits (510). Considering that also 1 bit is used to indicate the UE-RS pattern, the total overhead is reduced to 4 bits. For example, additional UE-RS parameters, such as UE-RS pattern, UE-RS sequence initialization ID parameters, may also be encoded in combination with UE-RS antenna ports and rank to be provided to UE 515 do.

In current LTE specifications, the antenna port value also includes the UE-RS spreading sequence and the scrambling sequence initialization ID used for transmission of UE-RS values corresponding to the antenna port, as well as the UE-RS pattern and UE-RS positions used It is recognized that it can be displayed.

It is also appreciated that a joint indication of UE-RS pattern, rank and antenna ports may also be considered. For example, antenna ports {2, 3} with rank 2 may not be used with UE-RS pattern A shown in FIG. These constraints may additionally be used in the joint encoding of the UE-RS pattern, rank and antenna ports.

It is additionally recognized that the above given examples for joint encoding of UE-RS parameters are for a maximum rank 4 transmission, but it is to be appreciated that the same principles can act on higher ranks or different assumptions about the number of UE- It is clear. Additionally, it is appreciated that while the examples given are for dynamic signaling using DL acknowledgment, some aspects of such signaling may be done in a quasi-static manner, while others may be done dynamically. This may in fact be useful to proceed to higher transmission ranks (e. G., Above rank 4).

It is understood that the particular order or hierarchy of steps in the disclosed processes is an example of exemplary methods. It is understood that, based on design preferences, a particular order or hierarchy of steps in the processes may be rearranged while remaining within the scope of this disclosure. The appended method claims present elements of the various steps in a sample order and are not intended to be limited to the particular order or hierarchy presented.

Those skilled in the art will appreciate that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, Light fields or light intensities, or any combination thereof.

Those skilled in the art will further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both will be. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure.

The various illustrative logical blocks, modules, and circuits described in connection with the embodiments disclosed herein may be implemented or performed with a general purpose processor, a digital signal processor ("DSP"), an application specific integrated circuit ("ASIC" Arrays ("FPGA ") or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but, in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

The steps of an algorithm or method described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art . An exemplary storage medium is coupled to the processor such that the processor can read information from, and write information to, the storage medium. Alternatively, the storage medium may be integrated into the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Accordingly, this disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (70)

A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE)
Including in the encoded information a bit sequence that jointly encodes an indication of a transmission rank with at least one parameter associated with the user-specific reference signal; And
And transmitting the encoded information within a payload of a downlink control channel.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). The method according to claim 1,
Wherein the at least one parameter comprises an indication of antenna ports used for transmission of the user-specific reference signal to the UE,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 3. The method of claim 2,
Wherein the at least one parameter further comprises a time-frequency resource pattern that characterizes the user-
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 3. The method of claim 2,
Wherein the bit sequence comprises 2 bits representing the transmit rank and 2 bits representing a start port of the antenna ports,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 5. The method of claim 4,
Wherein the bit sequence further comprises a bit representing a time-frequency resource pattern characterizing the user-specific reference signal,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 3. The method of claim 2,
Wherein the bit sequence comprises a plurality of bits collectively representing the transmit rank and an indication of the antenna ports,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). The method according to claim 6,
Up to four (4) antenna ports are used for transmission of the user-specific reference signal,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 8. The method of claim 7,
The plurality of bits comprising:
Wherein the transmission rank is 1 and a particular one of the four (4) antenna ports is used to transmit the user-specific reference signal;
Wherein the transmission rank is 2 and two of the four (4) antenna ports are used to transmit the user-specific reference signal;
Wherein the transmission rank is 3 and three of the four (4) antenna ports are used to transmit the user-specific reference signal; And
Wherein the transmission rank is 4 and each of the 4 (4) antenna ports is used to transmit the user-specific reference signal
Lt; RTI ID = 0.0 > 3, < / RTI >
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). The method according to claim 1,
Further comprising providing an indication of a UE-RS pattern within the encoded information.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). The method of claim 3,
Wherein the at least one parameter further comprises at least one of a UE-RS sequence initialization ID and a total number of UE-RS ports allocated to the UE.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). CLAIMS 1. A method for wireless communication,
Receiving, on a downlink control channel, encoded information associated with a user-specific reference signal associated with a user equipment (UE), the encoded information including at least one parameter associated with the user- And a bit sequence encoding in cooperation with the bit sequence; And
And decoding the encoded information.
Method for wireless communication. 12. The method of claim 11,
Wherein the at least one parameter comprises an indication of antenna ports used for transmission of the user-specific reference signal to the UE,
Method for wireless communication. 13. The method of claim 12,
Wherein the at least one parameter further comprises a time-frequency resource pattern that characterizes the user-
Method for wireless communication. 12. The method of claim 11,
Wherein the bit sequence further comprises a bit representing a time-frequency resource pattern characterizing the user-specific reference signal,
Method for wireless communication. 13. The method of claim 12,
Wherein the bit sequence comprises a plurality of bits collectively representing the transmit rank and an indication of the antenna ports,
Method for wireless communication. 12. The method of claim 11,
Further comprising determining an indication of a UE-RS pattern in the encoded information.
Method for wireless communication. 12. The method of claim 11,
Wherein the at least one parameter further comprises at least one of a UE-RS sequence initialization ID and a total number of UE-RS ports allocated to the UE.
Method for wireless communication. An apparatus for wireless communication,
Means for selecting a user-specific reference signal (UE-RS) parameter;
Means for jointly encoding a selected UE-RS parameter with at least one associated UE-RS parameter; And
Means for transmitting jointly encoded UE-RS parameters in a downlink control channel to a user equipment (UE) associated with the UE-RS.
Apparatus for wireless communication. 19. The method of claim 18,
Wherein the selected UE-RS parameter comprises a transmission rank,
Apparatus for wireless communication. 19. The method of claim 18,
The selected UE-RS parameter includes a UE-RS pattern.
Apparatus for wireless communication. 20. The method of claim 19,
Wherein the at least one associated UE-RS parameter comprises an indication of a set of antenna ports used for transmission of the UE-RS to the UE.
Apparatus for wireless communication. 22. The method of claim 21,
Wherein the means for communicating comprises means for associating a transmission rank with the set of antenna ports.
Apparatus for wireless communication. 23. The method of claim 22,
Wherein the means for associating comprises means for enumerating the antenna ports in the set of antenna ports with successive indices.
Apparatus for wireless communication. 24. The method of claim 23,
Wherein the means for jointly encoding comprises means for providing a bit sequence that encodes an association between the transmission rank and the set of antenna ports.
Apparatus for wireless communication. 25. The method of claim 24,
Wherein the bit sequence comprises a plurality of bits collectively representing the transmit rank and the set of antenna ports,
Apparatus for wireless communication. 26. The method of claim 25,
Wherein the bit sequence further comprises bits representing a UE-RS pattern,
Apparatus for wireless communication. 22. The method of claim 21,
Wherein the transmission rank corresponds to a cardinality of the set of antenna ports,
Apparatus for wireless communication. 22. The method of claim 21,
Wherein the at least one parameter further comprises at least one of a UE-RS sequence initialization ID and a total number of UE-RS ports allocated to the UE.
Apparatus for wireless communication. 24. A computer readable storage medium for use in a wireless communication system,
Instructions for causing at least one computer to select a transmission rank;
Instructions for causing the at least one computer to associate the selected transmission rank with at least one parameter associated with a user-specific reference signal (UE-RS); And
Instructions for causing the at least one computer to provide a joint indication of the rank and the at least one parameter to reduce overhead in a downlink control channel.
Computer readable storage medium. 30. The method of claim 29,
Further comprising instructions for causing the at least one computer to select a UE-RS pattern,
Computer readable storage medium. 30. The method of claim 29,
Wherein the at least one parameter comprises a set of antenna ports enumerated in successive indices,
Computer readable storage medium. 32. The method of claim 31,
Instructions for causing the at least one computer to provide the common indication provide a bit sequence that encodes an association between the transmit rank and the set of antenna ports,
Computer readable storage medium. 33. The method of claim 32,
Wherein the bit sequence comprises a plurality of bits collectively representing the transmit rank and the set of antenna ports,
Computer readable storage medium. 34. The method of claim 33,
Wherein the bit sequence further comprises a bit representing a UE-RS pattern characterizing the UE-RS,
Computer readable storage medium. 34. The method of claim 33,
Wherein the bit sequence further comprises bits representing the UE-RS pattern,
Computer readable storage medium. 34. The method of claim 33,
Wherein the bit sequence further comprises at least one bit representing UE-RS sequence initialization parameters.
Computer readable storage medium. 32. The method of claim 31,
Wherein the at least one parameter further comprises at least one of a UE-RS sequence initialization ID and a total number of UE-RS ports allocated to the UE.
Computer readable storage medium. Apparatus for facilitating provision of encoded information associated with a user-specific reference signal (UE-RS) associated with a user equipment (UE)
A processor,
The processor comprising:
Embedding in the encoded information a bit sequence that jointly encodes an indication of a transmission rank with at least one parameter associated with a user-specific reference signal; And
And to transmit the encoded information within a payload of a downlink control channel.
An apparatus for facilitating provision of encoded information associated with a user-specific reference signal (UE-RS) associated with a user equipment (UE). 39. The method of claim 38,
Wherein the processor is further configured to include bits representing the UE-RS pattern in the encoded information,
An apparatus for facilitating provision of encoded information associated with a user-specific reference signal (UE-RS) associated with a user equipment (UE). An apparatus for wireless communication,
A processor,
The processor comprising:
On a downlink control channel, encoded information associated with a user-specific reference signal associated with a user equipment (UE), the encoded information including at least one parameter associated with the user- Comprising: a bit sequence that is jointly encoded; And
And configured to decode the encoded information,
Apparatus for wireless communication. 41. The method of claim 40,
Wherein the at least one parameter is indicative of antenna ports used for transmission of the user-specific reference signal to the UE; And
At least one of a UE-RS sequence initialization ID and a total number of UE-RS ports allocated to the UE
≪ / RTI >
Apparatus for wireless communication. An apparatus for wireless communication,
Means for receiving, on a downlink control channel, encoded information associated with a user-specific reference signal associated with a user equipment (UE), the encoded information including an indication of a transmission rank as at least one A bit sequence encoding in cooperation with a parameter; And
And means for decoding the encoded information.
Apparatus for wireless communication. 43. The method of claim 42,
Further comprising means for determining an indication of a UE-RS pattern in the encoded information.
Apparatus for wireless communication. 43. The method of claim 42,
Wherein the at least one parameter comprises:
An indication of antenna ports used for transmission of the user-specific reference signal to the UE; And
At least one of a UE-RS sequence initialization ID and a total number of UE-RS ports allocated to the UE
≪ / RTI >
Apparatus for wireless communication. A computer-readable storage medium that facilitates providing encoded information associated with a user-specific reference signal (UE-RS) associated with a user equipment (UE)
Instructions for causing at least one computer to include in the encoded information a bit sequence that jointly encodes an indication of a transmission rank with at least one parameter associated with the UE-RS; And
Instructions for causing the at least one computer to transmit the encoded information within a payload of a downlink control channel.
Computer readable storage medium. 46. The method of claim 45,
Further comprising instructions for causing the at least one computer to select a UE-RS pattern,
Computer readable storage medium. 46. The method of claim 45,
Wherein the at least one parameter comprises a set of antenna ports enumerated in successive indices,
Computer readable storage medium. 49. The method of claim 47,
Further comprising instructions for causing the at least one computer to associate the transmission rank with the set of antenna ports.
Computer readable storage medium. A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE)
Selecting a transmission rank;
Associating the transmission rank with at least one parameter associated with the user-specific reference signal (UE-RS);
Providing a common indication of the rank and the at least one parameter, the set of scheduling constraints being selected to reduce overhead in a downlink control channel; subject to a set of scheduling constraints; And
And transmitting the common indication within the downlink control channel.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 50. The method of claim 49,
Wherein the at least one parameter comprises a set of antenna ports used for transmission of the user-specific reference signal to the UE,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 51. The method of claim 50,
Wherein the providing step comprises selecting a constrained set of antenna ports for inclusion in the set of scheduling constraints.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 52. The method of claim 51,
Wherein the at least one parameter further comprises a UE-RS pattern,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 53. The method of claim 52,
Wherein the step of selecting comprises determining, based on the transmission rank and the UE-RS pattern,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 54. The method of claim 53,
Wherein the selecting is further based on a maximum number of antenna ports supported by the UE,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 54. The method of claim 53,
Wherein the selecting is further based on a maximum number of UEs that can be multiplexed,
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 50. The method of claim 49,
Wherein the providing step comprises selecting a transmission mode for inclusion in the set of scheduling constraints.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 57. The method of claim 56,
Wherein the transmission mode includes one of SU-MIMO, MU-MIMO, and Cooperative MIMO.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 50. The method of claim 49,
Further comprising performing scheduling decisions for one or more other UEs based on the set of scheduling constraints.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 59. The method of claim 58,
Wherein the providing step comprises selecting the UE-RS pattern and the at least one parameter based on the scheduling decisions.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 50. The method of claim 49,
Wherein the providing step comprises selecting a set of scheduling constraints to guide channel and interference estimation and demodulation.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 58. The method of claim 57,
Wherein the providing step includes limiting a plurality of layers assigned to the UE in at least one of an MU-MIMO mode or a cooperative MIMO mode.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 62. The method of claim 61,
Wherein the limiting step comprises assigning one antenna port per transmission rank.
A method for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 10. Apparatus for facilitating provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE)
Means for selecting a transmission rank;
Means for associating the transmission rank with at least one parameter associated with a user-specific reference signal (UE-RS);
Means for providing a joint indication of the rank and the at least one parameter, subject to a set of scheduling constraints, the set of scheduling constraints being selected to reduce overhead in a downlink control channel; And
And means for transmitting the common indication within the downlink control channel.
A device that facilitates provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). 64. The method of claim 63,
And means for performing scheduling decisions for one or more other UEs based on the set of scheduling constraints.
A device that facilitates provision of encoded information associated with a user-specific reference signal associated with a user equipment (UE). CLAIMS What is claimed is: 1. A method for facilitating wireless communication in a user equipment (UE)
Receiving a joint indication of at least one scheduling parameter and at least one parameter associated with a user-specific reference signal (UE-RS); And
And performing a channel or interference estimate based at least in part on the at least one scheduling parameter.
A method for facilitating wireless communication in a user equipment (UE). 66. The method of claim 65,
Wherein the at least one scheduling parameter is associated with a total number of UE-RS ports scheduled in a subframe,
A method for facilitating wireless communication in a user equipment (UE). 66. The method of claim 65,
Further comprising performing a demodulation operation based at least in part on the at least one scheduling parameter.
A method for facilitating wireless communication in a user equipment (UE). 1. Apparatus for facilitating wireless communication at a user equipment (UE)
Means for receiving a joint indication of at least one scheduling parameter and at least one parameter associated with a user-specific reference signal (UE-RS); And
And means for performing channel or interference estimation based at least in part on the at least one scheduling parameter.
A device that facilitates wireless communication at a user equipment (UE). 69. The method of claim 68,
Wherein the at least one scheduling parameter is associated with a total number of UE-RS ports scheduled in a subframe,
A device that facilitates wireless communication at a user equipment (UE). 69. The method of claim 68,
Further comprising means for performing a demodulation operation based at least in part on the at least one scheduling parameter.
A device that facilitates wireless communication at a user equipment (UE).

Images